You can fit a Rohloff Speed Hub 14 to any frame end, dropout or other frame-end arrangement you can think of, including those that only the bicycle historians among us even know about. Rohloff has bent over backwards to make torque arms, monkey bones, speedbones and a wide variety of other unobtrusive torque arms/jockey wheel avoiders to enable the fitting of their hub to the least likely candidates. Rohloff also designed, and gives away the production blueprints free of charge to manufacturers, it's own very convenient OEM slider-holder rear end and the sliders which act as their own ultra-compact torque resistors while mounting everything including disc brakes neatly and very conveniently. The image below, from Rohloff's site, is just the opening page of an aladin's cave of Rohloff Speed Hub 14 mashups (if you don't know what a mashup is, ask your grandson -- Rohloff refuses to be left behind the times!).
(http://www.coolmainpress.com/miscimage/andre_jute_rohloff_speed_hub_finder_800pxw.jpg) (https://www.rohloff.de/en/service/search/speedhub-finder/)
GO TO THE ROHLOFF SPEED HUB FINDER (https://www.rohloff.de/en/service/search/speedhub-finder/) or just click the image to be whooshed there. If you see a partially blank screen rather than a little man on a bike or "Click to use Flash", you need to install Adobe's free utility Flash to use the interactive calculator which takes you to the Rohloff Speed Hub 14 model and dedicated components for each dropout/frame end. (You should click to use Flash only once or manually disable it afterwards: it is a security hazard.)
IanW says: "In my opinion the sliding rear-wheel drop-out is probably the simplest, the chain tensioner is the laziest, and the eccentric bottom bracket is the most aesthetically pleasing." That's probably right. But one could add that the sliding Rohloff axle, torque resistor and disk brake mount, all in one, is the most versatile as well as the simplest.
Enjoy!